What Spread Firefox called The March to 10 Million Downloads of the Firefox browser has already passed 20 million. This is several times the number of Mac OS X users, and in a couple of years, at the current rate, it could be approaching Windows XP SP2....

Of course, there's no reason why the adoption of Firefox shouldn't speed up. The almost universal penetration of Macromedia Flash illustrates that there's really no barrier to Windows users downloading whatever software they like, despite the opinions of the US Justice Department.